Compressor valve structure



March 28, 1939'. r c, 5 CODY 2,151,7 46 5 COMPRES SOR VALVE S TRUCTURE Filed July 14, 1936 WITNESSES: F I G INVENTOR CLIFFORD 5. Co y.

.15 description and claims taken in connection with than the diameter of the cylinder II, and at the 15 latented Mar. 28, 1939 v v i I 2,151,746

UNITED .STATES PATENT OFFICE COMPRESSOR VALVE STRUCTURE Clifford S. Cody, East Springfield, Mass., assignor to Westinghouse Electric & Manufacturing Company, East Pittsburgh, Pa., a corporation of Pennsylvania Application July 14, 1936, Serial No. 90,453

10 Claims. (01. 230-228) My invention relates to a valve structure for and resilient metal, such as Swedish steel, is cut compressors or the like, and it has for an object as shown in Fig. 4 to provide a tongue or flap to provide an improved valve structure. l9. The latter has an enlarged free end 20, which A further object is to provide suction and disis circular and of suflicient diameter to close the 5 charge valves of adequate flow areas. port l8 in the valve plate 15. The. port I8 and 5 Another object is to reduce the volumetric free end 20 of the flap I9 are so positioned with clearance of the compressor, that is, the space respect to the cylinder II that the tip of the flap between the piston and the discharge valve at projects slightly beyond the cylinder II, as shown the end of the compression stroke. in Figs. 3 and 6. A recess 2| is formed in the 10 A further object is to provide increased valve cylinder member to 'argommodate said projecting 10 opening movement of the suction valves withou tip, and the lower side of this recess constitutes increasing the stress.' v a stop for limiting the downward movement of These and other objects are eifected by my the free end of the flap l9. invention as will be apparent from the following The flap I9 is of substantially greater length the accompanying drawing, forming a. part of end at which it is connected to the sheet member this application, in which: V I4, it projects considerably beyond the cylinder Fig. 1 is a plan view of the valve structure, a as shown in Figs. 3 and 6. The upper surface of part of the compressor, with the cylinder head the cylinder member I0 is relieved, as indicated 2 removed, as seen along the line II of Fig. 3; at 22 in Figs. 3 and 6 to permit this projecting Fig. 2 is a section, taken on the line IIII of portion of the flap I9 to move away from the Fig. 1, showing a discharge valve; valve plate l5. The flap I9 is thus free-to flex Fig. 3 is a section, taken on the line III-III along a long radius of curvature when the same of Fig. 1, showing the valve structure and a is moved to open the suction port I8. The free 25 portion of the compressor; end 20 of the flap l9 may thus move a substantial 25 Fig. 4 is a plan view of the sheet member condistance away from the valve plate l5 to provide taining the movable element of the suction valve; adequate opening for flow of low pressure vapor Fig. 5 is a plan view of the movable elemen duringthe suction stroke, without sharp bending of the two discharge valves; and, of the flap l9. Adequate flow area through the Fig. 6is a plan view as seen along the line suction port is thus obtained while at the same 30 VIVI of Fig. 3. time providing long life of the flap l9. Referring to the drawing in detail, I show, in The relieved surface 2-2 may be of any suitable Figs. 1 and 3, a portion of a refrigerant comform. It may be of circular arc form conforming pressor in which my novel valve structure is emto the circular are along which the flap l 9 is bent bodied. The compressor includes a cylinder when the tip thereof touches the lower side of member I!) having a cylinder I I provided the recess 2|, or it may be formed along a straight therein and a piston l2 operating in the line so that the edge at the cylinder II just cylinder H. Thecylinder member is formed touches or nearly touches the flap l9 when the with a portion l3 projecting laterally from" the latter is so bent. The relieved portion'preferably 4O cylinder at the upper end thereof. A sheet metal extends to the right nearly to the junction be- 40 member l4, shown in Fig. 4, is placed against the tween the flap l9 and the-remainder of the sheet top of the cylinder member III, a valve *plate 15 metal member l4. j is placed on top of the sheet member 14, and a To provide for the discharge valves, the valve cylinder head I6 is positioned on top ofthe valve plate I5 is formed with a depression or recess plate IS with a gasket l5 preferably inserted 23 in its upper surface, the contour of the recess 45 therebetween. The head I6 is bolted to the cylbeing shown in Fig. 1. The recess is formed with inder member III, the positions of the bolts being an inclined surface 24 as will .be seen from Figs. indicated in Fig. 1 by the bolt-holes l1, and the 2 and 3. At the lowermost portion of the incylinder member In. The sheet member I4 and clined surface, where the recess thus forms a the valve plat 5 are thus p d we the portion of valve plate of minimum thickness, the head and the cylinder member. valve plate is formed with two discharge ports The valve plate 5 is formed With a Suction 25 located on opposite sides of the flap I 9. Two port l8. communicating with the cylinder and discharge valve elements 26 comprising strips of disposed adjacent one side thereof. The sheet flexible thin sheet metal such as Swedish steel, member I which is preferably made of a strong are disposed along the inclined surfaces, extend- 55 ing in an inclined direction, that is, in the direction of incline of the surface 2|. The lower or free ends of the valve strips shown at the lefthand end of the drawing, are adapted to close the upper ends of the ports-25, the inclined surface being formed with lands or raised surfaces around the edge of the ports '25 so that the valve elements 26 actually contact only along the narrow surfaces of these lands.

The opposite ends of the valve elements 26 are fixed against the upper end of the inclined surface, at a point adjacent the top surface of thevalve plate. They are clamped between the inclined surfaces of the valve plate and a stop member 21, the latter being secured to the valve plate by means of a screw 28 and a nut 29. The valve elements 26 and thestop member 21 are positioned in proper. relation to the valve plate l5 by means of pins 30, which are inserted in registering openings 3| in the stop member, the valve elements 26, and the valve plate l5. The upper ends of the openings 3| in the stop member 21 are closed by the nut 29. The lower side 32 of the stop member 21 constitutes a. stop for the discharge valve elements 26 in valve opening position. Grooves 32' are formed in said lower side 32 to minimize the suction effect of the stop member 21 tending to hold the valve element 26 in open position. Said lower side 32 of the stop member 21 is curved along a circular arc of sufiiciently long radius so that the discharge elements 25 may flex along said arc, thereby avoiding any sharp bending of these valves. As will be noted from Fig. 4, the sheet member I has openings 33 registering with the ports 25 to provide unrestricted communication between the cylinder and thedischarge ports 25. The valve plate I5 is formed with a rib 34 between the discharge ports 25 to provide increased strength for the valve plate in the region of the portion of reduced thickness.

By providing the recess 23 to depress the discharge valves, the volume of space comprising the discharge ports 25 is greatly reduced. In

this way, I am able to greatly reduce the volumetric clearance of the compressor, that is, the spade between the piston and the discharge valves. This space contains compressed gas at the end of the discharge stroke, which compressed gas re-expands and fills a portion of the volume of the cylinder upon the suction stroke of the piston. The volume of the re-expanded gas decreases, by the same amount, the quantity of low pressure gas thatis drawn into the cylinder to be compressed and thus reduces the V01? umetric efliciency of the compressor. Thus, by reducing the volume of the discharge ports 25 to a minimum, the amount of such re-expansion is minimized and the volumetric efllciency of the compressor is increased.

By disposing the ports 25 on opposite sides of the flap I9, I avoid conflict with the flap l9 and make advantageous use of that portion of the end of the cylinder which-is not required for the suction valve. It will thus be seen that I have provided an advantageous arrangement of suction and discharge valves, whereby adequate fiow area of both suction valve and discharge valve is provided.

The cylinder head I6 is provided with a suction passage 35, one end of which is adapted to be connected to a suction conduit 36 and the other end of which registers with the suction port l8. It is also formed with a recessed chamber 31 registering with the recess or depression 23 in the valve plate l5 and accommodating the nut 29 and a portion of the stop member 21'. A passage 33 leads from the chamber 31 and connects with a discharge conduit 39. The integral portion of the head between the passage 35 and the chamber 31 forms a partition 4|.

While the cylinder head and the valve plate have been shown as separate parts, it will be apparent that they may be made in one piece without departing from the invention.

While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited,but is susceptible of various changes and modifications without departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as areimposed by the prior art or as are specifically set forth in the ap-- pended claims.

What I claim is:

1. In a compressor or the like, the combination of a cylinder member having a cylinder formed therein, an end member secured to said cylinder member for closing one end of said cylinder and having a section port formed therein adjacent one side of the cylinder; and a resilient valve reed or strip disposed between said members, said valve strip having a free end movable into the cylinder and, cooperating with the valve strip may flex along a long radius of curvature upon valve opening.

2. In a compressor or the like, the combination of a cylinder member having a cylinder formed therein, a valve plate disposed against the cylinder member at the end of said cylinder, a resilient valve strip extending across the end of the cylinder adjacent the valve plate and extending beyond the cylinder at each end, said valve strip being fixed adjacent one end and the other end being free, the free end being movable into the cylinder, said cylinder member having a recess adjacent said fixed end to permit the valve strip to flex away from said valve plate and having a recess adjacent the free end to limit movement thereof away from said valve plate, the valve plate having a port cooperating with the free end of said valve strip to form a suction valve for the compressor.

3. In a valve structure for a compressor or the like, the combinationpf a valve plate, said valve plate having substantially parallel opposite surfaces, a depression formed in one of said surfaces to provide a portion of reduced thickness of valve plate, and a port extending through said portion of reduced thickness; and a resilient valve reed or strip having a free end adapted to cooperate with said port to form a discharge valve for the comto provide a portion of reduced thickness of valve plate, said depression having a surface inclined from the bottom of the depression to a point adjacent said one surface, and a port extending through a portion of the valve plate of minimum thickness adjacent the lower end of the inclined surface; and a resilient valve reed or strip disposed along said inclined surface, said valve strip being secured to the valve plate adjacent the uppermost portion of the inclined surface, and the opposite end being free to cooperate with said port to form a discharge valve for the compressor.

5. In a compressor or the like, the combination of a cylinder member having a cylinder formed therein, a valve plate located to close one end of said cylinder and having formed therein a discharge port communicating with said cylinder, said valve plate being recessed on the side remote from the cylinder in the region surrounding said discharge port, and a resilient valve strip fixed at one end and having a free end extending into said recess and cooperating with said discharge port to form a discharge valve for the compressor.

6. In a compressor or the like, the combination.

of a cylinder'member having a cylinder formed therein; a valve plate closing one end of said cylinder and having formed therein a discharge port communicating with said cylinder, said valve plate being recessed on the side remote from the cylinder in the region surrounding said discharge port to provide a valve plate portion of reduced thickness; and a resilient valve reed or strip having a free end extending into said recess and cooperating with said discharge port to form a discharge valve, said valve strip extending in an inclined direction from said discharge port to a portion of the valve plate of greater thickness and being fixed to said portion of greater thickness.

7. In a compressor or the like, the combination of a member having a cylinder therein, a valve plate disposed against said cylinder member at one end of said cylinder, a resilient suction valve strip disposed between said .plate and said cylinder member and extending across the cylinder, one

end of the valve strip being fixed and the other end being free, said valve plate having a suction port cooperating with the free end of said valve strip to provide a suction valve and having two discharge ports disposed on opposite sides of the valve strip, and discharge valve elements disposed on the opposite side of the valve plate and cooperating with said discharge ports to provide discharge valves for the compressor.

8. In a compressor or the like, the combination of a member having a cylinder therein, a valve plate disposed against said cylindermember at one end of said cylinder, a resilient suction valve strip disposed between said plate and said cylinder member and extending across the cylinder, one end of the valve strip being fixed beyond the cylinder and the other end being free, said valve plate having a suction port cooperating with the free end of said valve strip to provide a suction vave and having two. discharge ports disposed on opposite sides of the valve strip, and discharge valve elements disposed on the opposite side of the valve plate and cooperating with said discharge ports to provide discharge valves for the compressor.

9. In a compresssor or the like, the combination of a member having a cylinder therein, a valve plate disposed against said cylinder member at one end of said cylinder, a resilient suction valve strip disposed between said plate and said cylinder member and extending across the cylinder, one end of the valve strip being fixed and the other end being free, said valve plate having a suction port cooperating with the free end of said valve strip to provide a suction valve and having two discharge ports disposed on opposite sides of the valve strip, said valve plate being recessed on the opposite side in the regions surrounding said discharge ports, and resilient discharge valve strips cooperating with said discharge ports on said opposite side of the valve plate to provide discharge valves for the compressor.

10. In a compressor or the like, the combination of a cylinder member having a cylinder formed therein, an end member secured to said cylinder member for closing one end of said cylinder and having a suction port formed therein, and a resilient valve reed or strip disposed between said members, said valve strip having one portion movable into the cylinder and cooperating with said port to form a suction valve for the compressor and having one end retained betweensaid members beyond the cylinder, said cylinder member being recessed to permit a portion of the valve strip between the cylinder and said one end to flex with said one portion upon valve opening, whereby the valve strip may flex along a long line of curvature upon valve opening.

CLIFFORD S. CODY. 

